A digital elevation model (DEM) identifies, for each identified location within a geographic region, an elevation at such location. Typically, locations are identified within the geographic regions at a particular resolution, such as every two meters. DEMs are commonly used, for example, by a simulator to determine the locations of objects in the simulated environment, and to depict the simulated environment to a user.
In some circumstances, it may be desirable or necessary for an application, such as a simulator, to process information regarding multiple elevations at the same identified location within a geographic region. For example, it may be desirable to know both a bathymetric elevation that identifies an ocean floor at a particular location, and an elevation of the ocean surface at that particular location, to properly simulate the environment. In order to determine such information, multiple different sources of data are accessed. The different sources of data may be at different resolutions, may be in completely different formats, and may require source-specific processing in order to calculate the desired elevation information. In a run-time environment it may be impractical, or impossible, to access multiple different sources of data and perform the necessary processing in order to generate the desired elevation information while concurrently providing a high-resolution simulation to a user who is moving about the simulated environment.